Direct-current transformer



April 27, 1937. B. SPRINGER DIRECT CURRENT TRANSFORMER Filed Sept. 29,1934 4 Sheets-Sheet 1 DIRECT CURRENT TRANSFORMER Filed Sept. 29, 1934 4Sheets-Sfieet 2 20 i f Al i9 0 a r April 27, 1937. s. SPRINGER 2,078,618

DIRECT CURRENT TRANSFORMER Filed Sept. 29. 1934 4 Sheets-Sheet 3 B. Sur-1h IN April 27, 1937. a. SPRINGER DIRECT CURRENT TRANSFORMER 4Sheets-Sheet 4 Filed Sept. 29, 1934 Patented Apr. 27, 1937 UNITED STATESPATENT OFFICE Application September 29, 1934, Serial No. 746,253 InGermany October 2, 1933 22 Claims.

My invention relates to improvements in direct current transformers andmethods for operating such transformers and has for its main object toprovide a transformer of this type having improved characteristics andhigh operating efliciency.

Further objects and advantages of the invention will be apparent fromthe detailed description hereafter presented in connection with theaccompanying drawings.

In accordance with the general method and apparatus forming the subjectof the invention, I provide a set of condensers connected with aplurality of movable contact elements, a load or output circuit, and aninput circuit carrying the low voltage to be transformed and means forperiodically operating said movable contacts for alternately placing thecondensers in parallel and in series in such a manner that they arecharged in parallel at low voltage from the primary circuit andthereafter discharged in series at high voltage upon the load circuit. Ifurthermore provide a suitable storage device such as an electriccondenser in the load circuit in such a manner that by choosing asufllcient rate of the charging and discharging periods a substantiallysteady output voltage is obtained.

It has already been proposed to transform direct current ofcomparatively low voltage into direct current of high voltage bycharging a set of condensers with a primary voltage to be transformed,and thereafter discharging the condensers 1 series. thus obta ned isequal to the number of condensers used multiplied with the primaryvoltage.

This method of transformation condensers is superior to the use ofrectifiers because it operates practically without loss. Heretoiore,direct-current transformers designed on this principle, however, werenot suited for use in practice due substantially to'the fact thatdifficulties were encountered in performing the necessary switchingoperations of the condensers and that the number of switching operationsper second should be very high if a continuous output voltage isdesired. Moreover, consideration must be given to the voltage applied tothe condensers which may amount to several thousands of volts, and tothe power consumption of the switching device which should be as low aspossible. In addition, switching devices as used heretofore, mostlycomprising rotary contact drums, have been found to be quiteunsatisfactory due to the fact that after a short period of operation,strips of conducting metal form between the individual metal contacts ofthe drum. resulting in shortcircuits. Moreover. rotary contact drums arenot reliable for continuous operation without 1 attendance.

Byprovidingatransformeraccordinltomy The total secondary voltage bymeans of invention as described, the above-mentioned drawbacks aresubstantially eliminated and reliable switching of the condensers isinsured.

Transformers according to my invention may be used in all cases where ahigh direct current voltage is required. Thus, high voltage current isrequired in systems for testing insulators and the like. Heretofore,crank inductors, which are inaccurate and expensive, or largegenerators, had to be used for obtaining comparatively high voltages.High voltage direct current is also required for operating gas dischargetubes for power and similar purposes. direct current voltage isrequired, for instance, for charging storage batteries-from a supplysystem having a, higher voltage, such as for heating vacuum tubes, etc.,in the operation of wireless transmitters or receivers.

I have shown in the accompanying drawings, various types of transformersembodying my invention and diagrams illustrating the operation accordingto the invention.

In the drawings:

Figures 1 and 2 are diagrams tively, condensers connected in series. a

Figure 3 diagrammatically illustrates a directcurrent step-uptransformer in accordance with the invention.

Figure 4 and Figure 5 show vertical and horizontal cross-sections,respectively of a constructional embodiment of a device according to theinvention.

Figure 6 is a diagram illustrating the operation of the device accordingto Figures 4 and 5.

Figures '1 and 8 show diagrams for step-down transformation in thecharging and discharging positions, respectively, of the condensers.

Figure 9 shows a cascade connection of condensers. i

Figure 10 shows another form of a switching ..device according to theinvention.

Figure 11 is a section on line XI-XII in F18- ure 10.

Figure 12 is an elevation showing certain parts of the device accordingto Figure 10.

Figure 13 is a section on line XIII-XIII in Figure 10.

Figure 14 is showing, respecparallel and in a diagram showingconnections for devices according to Figures 10 to 13.

Referring to the drawings, Figure 3, items I, 2 and 3 representindividual condensers of the transformer, it being understood that anynumber of such condensers may be provided. while item 4 is a collectingcondenser for maintaining a steady output voltage. Item 5 indicates aload circuit connected to the collecting condenler I. As is more thanone collecting condensermay be provided..or the collecting elmdenser maybe with altogether. Item Stepping down of peated in a known I indicatesthe supply or input circuit carrying the primary voltage to betransformed.

Figure 1 is a diagram showing the three condensers connected in parallelto the circuit O-in charging position, while Figure 2 shows the contheprimary voltage without loss and the high voltage direct current appliedto the load circuit I.

The periodic switching-over of the condensers from one position to theother position is carried out automatically and in rapid succession,such as by means of an arrangement illustrated in Figure 3. In thelatter, a plurality of groups of contact elements each comprising threecontact springs a, b, and c secured to blocks 'I of insulating materialare provided in circular arrangement as shown. The ends of the centralmovable springs of each group connected to thecondensers engage notches8 of a segmental element I fulcrumed at its center 9. The segmentalelement III is made of insulating material or the ends of the springs bmay be properly insulated. I have furthermore shown means foroscillating the element purpose with a rocker arm extension" II which ispartly or entirely of magnetic material and carries a balance weight atits extreme end. This arm is alternately attracted 'and released by anelectromagnet I2 whose coil II has one end connected to the arm asshown. Item I4 is a spring contact engaging the arm II as shown. Whenthe arm II is in the central position illustrated, an electric circuitis closed through contact I4, arm II, and the magnet coil", whereby themagnet attracts the arm, thus breaking the circuit of coil II. The armnow moves into the {opposite position, forcing back contact I4 andclosing the circuit, whereupon the cycle is remanner. When the arm IImoves to the left, the springs b engage the fixed contacts 0 and allcondensers I, 2 and 3 are connected in parallel to the primary orfundamental voltage circuit 6. The connection is now as shown in Figure-l and the condensers are charged. When the arm II moves to the right.the springs b engage the contacts a and the connection illustrated inFigure 2 is obtained whereby the total voltage of 'the condensers isapplied to the collecting condenser 4 supplying the load with thedesired voltage.

Thus, during each oscillation II, the collecting condenser is chargedafresh at high voltage. The velocity at which the segment oscillates islimited only by the charging period of the condensers which, however, isso short as to be negligible so that any pr ctically attainablefrequency of oscillation maybe used.

This method of switching has the additional advantage that the movablecontact members b have to move through short distances only in thenotches 0. The collecting condenser 4 and'the loadcircult I are never inconductive connection with the fundamental or Referring to Figures 41nd5 showing a structural embodiment of a switching apparatus according tothe invention, the contact springs a and c, "and the movable spring btherebetween are arranged one above the other and mounted in the walland distributed along the circummature 2| mounted at the Item 22 is acontact spring engaging the I0 provided for this of the segment ferenceof a cylindrical casing ii of insulating material, such as fibre.Mounted centrally on a shaft I6 between the contacts and movable membersare a pair of switching plates I1 and I8 of insulating material, and themovable members b are arranged to the two plates I I and II as shown. By-these means the shaft I 6 is resiliently supported by the movablemembers b and is moved up and down by an electromagnet attracting anarlower end of shaft I6. upper end of shaitIG which is in the neutralposition as shown. One end of the magnet coil 20 is connected to thearmature and the remaining end is connected to one pole of the source ofinput potential to be connected at 6. The other pole of the input sourceis connected to the spring contact 22; Thus, when the magnet 20 isexcited and armature 2| is attracted, the circuit is periodically brokenby contact 22 and the shaft.

with Figure 3.

Figure 6 shows the diagram of connections for Figures 4 and 5. Theprojecting ends of the contacts a, c and the movable members b areindicated by black dots. By the vibrating movement of shaft I6, themovable member b is alternately caused to engage contacts a and c, in asimilar manner as described for Figure 3, and the condensers I, areconnected and disconnected as described.

Another advantage of the device illustrated in Figures 4 to 6 is thefact that only small weights have to be moved for performing theswitching operation so that a small battery, such as an ordinary flashlight battery, may be used for energizing the magnet coil 20. Thevoltage of the battery is maintained constant by any suitable means toobtain a uniform oscillation and constant charging of the collectingcondenser 4. Another reason why the battery may be small is the factthat it is not necessary to start the movable members b which resonanceand amplitudes required for engaging the contacts a or c, respectively.

The method of stepping down direct current voltages .is illustrateddiagrammatically by Figunes 7 and 8. In the position shown in Figure 7,connected in series and charged at high voltage, and then, as shown inFigure 8, they are separated from the source of high voltage andconnected in parallel. As will be understood, a

left, the condensers I and III are connected in parallel and both to thevoltage supplied at the input terminals I which may be an availablesupply voltage, for instance 220 volt, to which the condensers arecharged. Upon the subsequent movement of movable members I02. I03 to theright, the condensers I06 and I01 are connected in series over contactsI08 and I08, so that a voltage of 440 is applied between the lead IIOconnected to contact, I08, and the lead III. The condenser II2 has thesame voltage applied to it, and when the movable members again move tothe left, the condenser H3 is connected in parallel to condenser II2.When the movable members I02, I03 again move to the right, condensersH2, '3 are connected in series so that the total voltage between theleads III, 0' is 880 volts in the example above given. In this mannerthe fundamental voltage is raised to a final voltage of 7040' byconnecting the condensers H4 and H5, H6 and III,-and H8 and H9alternately in parallel and in series, and the collecting condenser I towhich the load circuit I2I is connected is charged at this voltage. Itis understood that on account of the finite charging periods of thecondensers, a number of oscillations of the movable members I02, I03 arerequired before static conditions are attained requiring a few secondsfor the starting of the transformer.

It follows that by the novel connection, a thirty-two fold ratioisobtained instead of a ten-fold ratio obtained with the previousmethods. For a still higher ratio, a greater number of series-parallelgroups may be provided, or three or more condensers may be provided ineach group, the final voltage being equal to 1n wherein m is the numberof condensers in each group and n represents the number of groups used.For instance, ifgroups of three condensers are formed, the ratioincreases by a cubic law, that is, with five groups of three condenserseach the ratio would be 1:243.

The advantages of a system of this type are obvious. Another and veryimportant advantage of the invention is the fact that the number ofmovable contact members is reduced considerably so that the devicebecomes more simple and reliable.

Stepping-down may be performed on the same principle. The high voltageto be transformed has only to be connected to wires I2I while thecondenser I06 serves the collecting condenser for the load circuit.

The condensers should be adapted to the various voltages in such amanner that the capacity of-the condensers decreases as the'voltageincreases since the higher the voltage and the lower the currentintensity, the smaller the capacities required ior receiving, thevoltage impulses.

It is most important for the reliability of the devices described, thatno sparks should form between the movable contact members and thecooperating contacts as this would damage the contacts on account of thehigh number of operations. In the diagram, Figure 9, the contactsI04-I08, or I06-I88 carry the full voltage,

whereas the voltage between the contacts I32- NIL-I08, and I06-'I08 maynever attain amounts at which sparks will form because the condenserstransmit only part of their charge to the next steps. It has been foundin actual operation, however, that a closing spark occurs betweencontacts I04 and movable member I32 which is troublesome, particularlyat higher voltages. I have found that this closing spark is due to acertain leakage capacity which the condensers II8, I01, H3, H6 possessthrough their casing which is of the order of some 100 cm. and connectedto earth, or wire III. This leakage capacity is charged when the twocondensers H8 and H8 are connected in series, at the full voltage of therespective stage, say, 3520 volts so that upon the subsequent movementof member I02 to the left, there is a great voltage drop between themember and contact I04 which causes a spark to lump.

Sparking is eliminated according to my invention by connecting themovable contact members I02 to earth or to the wire III through a highresistance 222. While the contact member I02 moves from contact I08 tocontact I04, the leakage capacity is discharged and sparking isprevented. In Figure 9 the leakage capacity of the condenser where itoccurs, is indicated in dotted lines at 223.

Referring now to Figures 10 to 14, these show a switching deviceparticularly designed for cascade operation but equally suited for thesimple system described previously. Item I22 is a base plate in whichare inserted movable contacting members or springs I23 with terminalscrews I24 at their lower ends. The free end of each movable member I23projects between two contact elements I26 and I26 secured to a top plateI21 supported by posts I28, connecting the top and base plates as shown.A disk I28 of insulating material has its peripheral edge connected tothe springs I23 as shown. The posts I28 pass through openings of theplate I28, said openings being larger than the diameter of the posts asshown in Figure 11.. When disk I28 is rotated, the movable members I23engage one or the other contacts I26 and I26. The holes I30 for theposts I28 must be wide enough to provide suflicient clearance to insureengagement of the contacts I26 and I26. Tension is exerted on themovable members I23 when the disk I28 is turned but this is limited tothe portion of the members which is between base plate I22 and disk I28while the portions of the members which project from disk I28 aredisplaced practically without distortion. In order to dampen theprojecting portions 01' member I23, damping plates I3I may be arrangedat opposite sides thereof, as shown.

When the disk I28 is oscillated, the movable members I23 alternatelyengage the contacts I26 and I26. Any suitable means may be provided foroscillating the 'disk I28. Thus, the disk may be provided with a lug,not shown, which is struck by an oscillating hammer. In the exampleillustrated, oscillation of disk I28 is effected by an interruptercomprising a magnet coil I32 having core I33 with three extending armsas seen from Figure 11. The armatures consist of three pins I34 mountedupon the disk I28. When the core I33 attracts its three armatures I34,the disk I28 moves closer to one of the contacts, suchas I26. When thecoil I32 is deenergized, the elastic reaction of the movable contactingmembers I23 causes the disk I28 to return and the movable members I23 toengage contact I26. A spring I36, as shown in Figure 13, cooperatingwith a contact spring I23 serves to control the exciter circuit. in amanner similar as described hereinbefore.

The operation is as follows: current at first flows thru coil I32 (seeFigures 10 and 18), then thru spring I36 and contact spring I23, andback to the source of energy. While the spring I is in contact withspring I22, the exciter circuit is closed. The circuitis broken at theinstant when the springs I35 and I23 are separated by the movement ofdisk I29; Spring I23 swings back and the cycle is repeated. The springI35 may be adjusted by a set screw I36 mounted upon a bracket I31. Thecurrent consumption is very low so that a normal pocket lamp batterywill last for more than 1,000 hours.

A condenser is arranged between every two movable contacting membersI28, and connected thereto by screws I24. The condensers are not shownand itis understood that they may com- Drise several individualcondensers connected in parallel. The contacts I and I26 are connectedto each other in the manner illustrated in Figure 9.

It is understood that I am not in any way limited to any particular typeof condenser but may use any condensers desired.

I claim:

1. In a direct-current transformer, a primary circuit supplying avoltage to be transformed; a secondary circuit; a set of condensers; aplurality of movable contact members; a pair of cooperating contactelements for each movable member arranged at opposite sides of themovable member; and means for alternately placing said movable membersinto engagement with one of their cooperating contacts, the individualcontacts being so connected to said condensers and said circuits thatthe condensers are connected in parallel to said primary circuit whensaid movable members engage one of their cooperating contacts and thatthe condensers are connected in series to said secondary circuit whensaid movable members engage their other cooperating contact.

2. In a direct-current transformer, a load circuit; an equalizingcondenser connected across said load circuit; a primary circuitsupplying a fundamental voltage to be transformed; a set of condensers;a plurality of movable contact members; a pair of cooperating contactelements for each movable member arranged at opposite sides of saidmovable members; and means for alternately placing said movable membersinto engagement with one of their cooperating contacts, the individualcontacts being so connected to said condensers and said circuits thatsaid condensers are connected in paralel to said primary circuit whensaid movable members engage one of their cooperating contacts, and thatsaid condensers are connected in series to said. load circuit when saidmovable members engage the other of their cooperating contacts.

3. In a direct-current transformer, a load circuit; a primary circuitsupplying the fundamental voltage to be transformed; a plurality ofgroups of condensers; a plurality of movable contact members; a pair ofcooperating contacts for each movable member arranged at opposite sidesof the corresponding movable member; means for alternately placing saidmovable members into engagement with one of their cooperating contacts;further means including circuit connections for connecting theindividual condensers of each group in series and across one of thecondensers of the succeeding group in one of the contacting positions ofsaid members; and further means for connecting the condensers of eachgroup in parallel in the other contacting position of said movablemembers, said primary circuit being connected across a condenser of thefirst group and said load circuit being connected across the last groupof condensers.

4. In a direct-current transformer, a load circuit; a primary circuitsupplying the fundamental voltage to be transformed; a set ofcondensers; a plurality of movable contact members; a pair ofcooperating contacts for each movable member arranged at opposite sidesof the corresponding movable member; means for grounding said movablemembers through a high resistance: and means for alternately placingsaid movable members into engagement with one of their cooperatingcontacts, the individual contacts being so connected to said condensersand said circuits that the condensers are connected in parallel to saidprimary circuit when the movable members engage one of their individualcontacts, and that the condensers are connected in series to said loadcircuit when the movable members engage the other of their cooperatingcontacts.

5. In a direct-current transformer, a load circuit; a primary circuitsupplying-the fundamental voltage to be transformed; a plurality ofcondensers; a plurality of movable contact members; a pair of contactsfor each movable member arranged at opposite sides of the correspondingmovable member; an element operatively connected to said movable membersfor alternately placing them into engagement with one'of theircooperating contacts; and means for imparting oscillating movement tosaid element, the individual contacts being so connected to saidcondensers and said circuits that the condensers are connected inparallel to said primary circuit when said movable members engage one oftheir cooperating contacts, and that the condensers are connected inseries to said load circuit when said movable members engage the othercooperating contact. a

6. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a plurality of movable contact members, a pair of contacts for eachmovable member arranged at opposite sides of the corresponding movablemember; a vibrating element operatively connected tosaid movablemembersand being electrically insulated therefrom; and means for imparting'vibratory movement to said element for alternately placing said movablemembers into engagement with their cooperating contacts, the individualcontacts being so connected to said condensers and said circuits thatthe condensers are connected in parallel to said primary circuit whensaid movable members engage one of their cooperating contacts, and thatthe condensers are connected in series to said load circuit when saidmovable members engage the other cooperating contact.

7. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a plurality ofcondensers; a plurality of movable contact members; a pair of juxtaposedcontacts for each movable member arranged at opposite sides of thecorresponding member and distributed along the arc of a circle; avibratory element having recesses engaging said movable members; andelectromagnetic means for imparting vibrating movement to said elementfor alternately placing said movable members into engagement with one oftheir cooperating contacts, the individual contacts being so connectedto said condensers and said circuits that said condensers are connectedin parallel to said primary circuit when said movable members engage oneof their cooperating contacts, and that said condensers are connected inseries to said load circuit when said movable members engage their othercooperating contact.

8. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a plurality of flat contact springs; pairs of cooperating contactsassociated with each of said springs arranged sponding spring; anactuating element engaging the free ends of said springs; andelectromagnetic means for imparting vibrating movement transversely tosaid springs for alternately placing said springs into engagement withone of their cooperating contacts, the individual contacts being soconnected to said condensers and said circuits that said condensers areconnected in parallel to ,said primary circuit when said springsengageone of their cooperating contacts, and that said condensers areconnected in series to said load circuit when said springs engage theother cooperating contact.

9. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a base plate; a plurality of flat contacting springs having one endsecured to said base plate; a pair of cooperating contacts for eachspring arranged at opposite sides of the corresponding spring; anactuating member firmly connected to said springs; and means forapplying rotary vibrating movement to said member for alternatelyplacing said springs into engagement with one of the cooperatingcontacts, the individual contacts being so connected to said condensersand circuits that the condensers are connected in parallel to saidprimary circuit when said springs engage one of their cooperatingcontacts, and that the condensers are connected in series to said loadcircuit when said springs engage their other cooperating contact.

10. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a base plate; a plurality of flat contact springs having one end securedto said base plate; a pair of cooperating contacts for each springarranged at opposite sides of the corresponding spring; a disk havingits periphery connected to said springs with the contacting ends of saidsprings projecting beyond said disk; and means for applying rotaryvibrating movement to said disk for alternately placing said springsinto engagement with one of their cooperating contacts, the individualcontacts being so connected to said condensers and said circuits thatthe condensers are con nected in parallel to said primary circuit whensaid springs engage one of the individual contacts in each pair, andthat the condensers are connected in series to said load circuit whensaid springs engage the other individual contact.

11. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a base plate; a plurality of flat springs having one end secured to saidbase-plate and arranged along a substantially circular curve; a pair ofcooperating contacts for each spring arranged at opposite sides of thecorresponding spring; a disk having itsfperipheryconnected to saidsprings with the contacting ends of said springs projecting beyondsaiddisk; means for dampening the projecting ends of said springs; and meansfor applying rotary vibrating movement to said disk for alterat oppositesides of the correcontact members, further contacts being so connectedto said condensers and said circuits that the condensers are connectedin parallel to said primary circuit when said springs engage one oftheir cooperating contacts and that the condensers are connected inseries to said load circuit when said springs engage the othercooperating contact.

12. In a direct-current transformer, a load circuit; a primary circuitcarrying the fundamental voltage to be transformed; a set of condensers;a base plate; a plurality of contacting springs having one end securedto said base plate and ar-, ranged along a substantially circular curve;a pair of cooperating contacts for each spring arranged at oppositesides of the corresponding spring; a disk having its periphery firmlyconnected to said springs with the contacting ends of said springsprojecting beyond said disk; and electromagnetic vibrating means forapplying rotary vibrating movement to said disk for alternately placingsaid springs into engagement with one of their co operating contacts,the individual contacts being so connected to said condensers and saidcircuits that the condensers are connected in parallel to said primarycircuit when said springs engage one means for alternately placing saidmovable members into engagement with one of the individual contacts inthe corresponding pairs, further means including circuit connectionsforconnecting the individual condensers of each group in series andacross one of the condensers of the succeeding group in one of thepositions of said means for connecting the condensers in each group inparallel in the other contacting position of said movable contactmembers, said load circuit and said input circuits being eachconnectedacross a single condenser of the first of said groups andacross all the condensers in series of the last of said groups.

14. A direct current transformer comprising input and output operatingcircuits, a plurality of electrical condensers, a contacting mechanismhaving a base, a plurality of leaf springs circumferentially secured tosaid base, each pair of said springs being connected to the terminals ofsaid condensers, a pair of stationery contacts operatively associatedwith the free ends of said springs, the individual contacts in each pairbeing disposed at opposite sides of the corresponding spring, a discshaped actuating member firmly and circumferentially engaging saidsprings at a position intermediate said base and the free ends of saidsprings, and an electro-magnetic actuating device for imparting rotaryoscillating movement to said member for alternately placing said springsinto engagement with one of the associated stationary contacts, andfurther means including circuit connections from said stationary and inconnection with said operating circuits by the operation of saidactuating member whereby the input direct voltage is transformed to adifferent voltage by alternate charge and discharge of said condensers.

15. In a,direct current transformer as claimed in claim 14 in which saidelectro-magnetic mechanism comprises a magnetcore mounted concentricallyto said disc and having a plurality of radial extensions, and aplurality of pin-shaped armatures carried by said disc in operativerelation to said core extensions.

16. An energy conversion system comprising a low voltage direct currentsource; a plurality of 15 low voltage input condensers; a high voltageoutput condenser; a switching device having contact means for chargingsaid condensers by said source substantially in parallel at apredetermined position of said switching device; further contact meansof said switching device for thereafter connecting said condensers inseries and discharging them upon said high voltage condenser at asuccessive position of said switching device while simultaneouslydisconnecting said. input con- 26 densers from the low voltage sourceand means for periodically operating said switching device to obtain asubstantially steady output voltage from said high voltage condenser.

- i7. An energy conversion system comprising a 30 low voltage directcurrent source; a plurality of low voltage input condensers; a highvoltage output condenser; a switching device having contact means forcharging said condensers by said source substantially in parallel at apredetermined position of said switching device; further contact meansof said switching device for thereafter.

connecting said condensers in series and dischargciated with saidswitching members and circuit connections therefrom to said condensersfor s5 charging said input condensers by said source substantially inparallel at one position of said switching members and for thereafterdisconnecting said condensers from said source and ical vibrator.

19. An energy conversion device comprising a 7 low voltage directcurrent source; a plurality of low voltage input condensers; a highvoltage output condenser; a plurality of switching members;

a common shaft for operating said switching members in unison; avibrator mechanism actuating said shaft for moving said switchingmembers periodically between two positions; resilient contactsassociated with said switching members; and cooperating stationarycontacts and circuit connections thereto from said input condensers,said source and said output condenser, whereby at one position of saidswitching members said input condensers are connected to said lowvoltage source substantially in parallel and whereby at the otherposition of said switching members said input condensers are connectedin series and discharged upon said high voltage condenser.

20. In combination, a lowvoltage current source; a plurality of lowvoltage input condensers; a high voltage storage condenser; an

oscillating switching device having contact means and circuitconnections therefrom to said input condensers and said source forcharging said condensers by said source in parallel in one position ofsaid switching device; further contact means of said switching deviceand circuit connections therefrom to said input condensers and to saidstorage condenser for thereafter connecting said condensers in seriesand discharging them upon said storage condenser at the oppositeposition of said switching device while disconnecting said inputcondensers from said source, the frequency of charging and dischargingof said condensers and the capacity of said storage condenser being suchas to secure a substantially steady high voltage output potential fromsaid storage condenser.

21. An energy transfer system comprising a low voltage direct currentcircuit; a high voltage direct current circuit; a plurality of lowvoltage condensers; a high voltage condenser in said high voltagecircuit; a switching device having contact means for connecting saidcondensers to said low voltagecircuit in parallel at a predeterminedposition of said switching device; .further contact means of saidswitching device for thereafter connecting said low voltage condensersin series across said high voltage condenser at a successive position ofsaid switching device while simultaneously disconnecting said lowvoltage condensers from the low voltage circuit; and means forperiodically operating said switching device to secure a substantiallysteady energy transfer between said low voltage and said high voltagecircuits.

22..An energy transfer system comprising a low voltage direct currentcircuit; a high voltage direct current circuit; a plurality of lowvoltage condensers; a high voltage condenser in said high voltagecircuit; a switching device having contact means for connecting said lowvoltage condensers in parallel to said low voltage circuit at apredetermined position of said switching device further contact means ofsaid switching device for thereafter connecting said low voltagecondensers in series and across said high voltage condensers at asuccessive position f said switch-' ing device while simultaneouslydisconnecting said low voltage condensers from said low voltage source;and means for periodically operating sai switching device to secure asubstantially steady energy transfer between said low voltage and highvoltage circuits, said last means comprising an electro-mechanicalvibrator operating said switching device.

' BER'IfHOLD SPRINGER.

